Check engine ligh blinks going up hill sometimes

If you are talking about your check engine light that's blinking, that means you have a misfire big enough that if you continue driving your vehicle like that you can damage your catalytic converter. Get it checked asap

Check for trouble codes.

when engine light blink it is only one thing.......misfire you could have P0300,P0301 and so on
P0300 is multiple misfire
P0301 is cylinder no 1 misfire,the last number tell you the no cylinder
hope it helps

What type vehicle, year and model. Sounds like the vehicle is in limp mode. Something is wrong and the computer may be limiting performance so nothing else go wrong. Did she throw a code, check engine light blinking?..

first check to see what trouble code is coming up on the scanner

Check ignition wires for sparks jumping to grounds. If wires are old or leaking sparks, replace wires. let us know if this doesn't solve it.
Also, if engine ligh tis on, please have the car scanned and send us trouble codes. Autozone and Advance have free scan service,

With the ignition key off, Turn to the on then off then on position and leave it on and count the blinks with the engine light. This will be an engine code. Let me know what ya find out.

Have you had to add oil? The fact that it comes on going up hill would suggest it's the oil level.

on our 1997 it was a misfire and one of the ignition coils needed replaced.

sometimes when you are going up hill your check engine light or your oil light will come on because all of the oil is at the back of your oil pan.